Aegis, as stated in the Iliad, was carried by Zeus and Athena. It had been interpreted to be a shield or as an animal skin in the shape of a shield, sometimes bearing the head of a Gorgon.

Today, people use the word "aegis" to mean doing something under the protection of a powerful, knowledgeable, or benevolent source. The word aegis is identified with protection by a strong force with its roots in Greek mythology and adopted by the Romans. There are parallels in Norse mythology and in Egyptian mythology as well, where the Greek word aegis (a device to provide protection) is applied by extension.

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